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Space Weather and Radio Propagation
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Space Weather and Radio Signal Propagation - NW7US / SunSpotWatch.com
Space Weather and Radio Signal Propagation - NW7US / SunSpotWatch.com

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Here is a demonstration of using FLDigi software to work with Olivia on HF. Toward the end of the video, I decode a signal.

On some playback platforms, the audio is such that my voice is masked by the radio audio. I apologize. Next time I will ensure that the audio level from the radio is much lower.

Comments are welcome.

https://www.youtube.com/watch?v=ejSNfXiT8FE

73 de +NW7US
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A GREAT COMPROMISE: OLIVIA DIGITAL KEYBOARDING MODE ON SHORTWAVE HF

It is clear that we are approaching the end of current Sunspot Cycle 24, and are entering into the phase between cycles in which we may not see sunspots for great lengths of time (days, weeks, perhaps months). With this decrease in solar activity comes at least two changes: 1) the ionosphere dynamics change that includes lower maximum usable frequencies, shorter windows of "openings" over a given radio circuit's path, and, 2) the typical stability of a rarely-disturbed geomagnetic field. These and other factors significantly change the landscape of high-frequency (shortwave) radio-wave propagation.

In this challenging mix of real-world change, users of HF seek effective means of communications that rely on the ionosphere for long-distance (DX) radio-wave propagation. One digital mode is known as, Olivia.

Olivia is an MFSK–Multi-Frequency Shift Keying–radioteletype protocol designed to work in difficult conditions on shortwave bands. The Olivia digital mode is commonly used by amateur radio operators to reliably transmit ASCII characters over noisy channels using the high frequency (i.e., 3 MHz to 30 MHz; high-frequency, or HF; shortwave) spectrum. The typical Olivia signal is decoded when the amplitude of the noise is over three times that of the digital signal!

In 2005, SP9VRC, Pawel Jalocha, released to the world Olivia, a mode that he developed starting in 2003 to overcome difficult radio signal propagation conditions on the shortwave bands. By difficult, we are talking significant phase distortions, low signal-to-noise ratios (SNR), and multipath propagation effects. The Olivia-modulated radio signals are decoded even when it is ten to fourteen dB below the noise floor. That means that Olivia is decoded when the amplitude of the noise is slightly over three times that of the digital signal!

Read more, here: http://blog.nw7us.us/post/168515010062/olivia-digital-mode-great-compromise
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The link below is a video in which I demonstrate how to set the Reed-Solomon Identification (RSID) feature in Ham Radio Deluxe's Digital Master 780 module (HRD DM780). I encourage ALL operators in any digital mode such as Olivia, set the RSID feature on as shown in this example. In Fldigi, the RSID is the TXID and RXID (I believe).

Please make sure you are using the RSID (Reed Solomon Identification - RSID or TXID, RXID) option in your software. RSID transmits a short burst at the start of your transmission which identifies the mode you are using. When it does that, those amateur radio operators also using RSID while listening will be alerted by their software that you are transmitting in the specific mode (Olivia, hopefully), the settings (like 8/250), and where on the waterfall your transmission is located. This might be a popup window and/or text on the receive text panel. When the operator clicks on that, the software moves the waterfall cursor right on top of the signal and changes the mode in the software. This will help you make more contacts!

+ NOTE: MixW doesn't have RSID features. Request it!

+ 2nd Note: A problem exists in the current paid version of HRD's DM780: the DM780 RSID popup box to click does not work. HRD support is aware of the problem. You can still use the textual version that you can select in the settings so that it appears in the receive text areas. If you click the RSID link that comes across the text area, DM780 will tune to the reported signal, and change to the correct settings.

Video:

https://www.youtube.com/watch?v=lBIacwD9nNM

73 de +NW7US

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Eavesdropping on Olivia
Today (18 NOV 2017) on 20 meters

Olivia is alive and well on HF, across the world. No, it is not a hit-and-run wallpaper-making mode like FT8. Rather, it is a conversational mode (aka ragchewing mode). Yes, it is slower than PSK31. But, Olivia handles HF propagation challenges that kill PSK31 (like trans-polar propagation).

We have a Groups.io mailing list dedicated to Olivia at https://groups.io/g/Olivia

And, on Facebook, we are at https://www.facebook.com/groups/olivia.hf/

https://www.youtube.com/watch?v=2lv9dshac78

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Eavesdropping on Olivia
Today (18 NOV 2017) on 20 meters

Olivia is alive and well on HF, across the world. No, it is not a hit-and-run wallpaper-making mode like FT8. Rather, it is a conversational mode (aka ragchewing mode). Yes, it is slower than PSK31. But, Olivia handles HF propagation challenges that kill PSK31 (like trans-polar propagation).

We have a Groups.io mailing list dedicated to Olivia at https://groups.io/g/Olivia

And, on Facebook, we are at https://www.facebook.com/groups/olivia.hf/

https://www.youtube.com/watch?v=2lv9dshac78

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The most powerful X-ray flare of this sunspot cycle (Cycle 24), peaking at 12:12 UTC with the magnitude of X9.3, possibly emitted a coronal mass ejection (CME). It might be Earth-directed.

Stay tuned!

http://SunSpotWatch.com/swc

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We are in the midst of a geomagnetic storm caused by the passage of the CME produced by the x-ray flare:

AURORA ALERT: The sunspots of Active Region (AR) 2665 produced a powerful M2-class solar flare which lasted for more than two hours on July 14, 2017.

WATCH: https://youtu.be/GTK1kz5oGi8

The flare was associated with a 10cm Radio Burst (TenFlare) lasting 44 minutes and measuring 130 solar flux units (SFU). A Type IV radio emission was also logged at 02:02 UTC. Updated imagery by SDO suggests a coronal mass ejection (CME) is associated with these events.

Earth-facing coronagraph imagery reveals a bright coronal mass ejection (CME) directed mostly to the west. The STEREO Ahead spacecraft confirms that a halo CME is associated with this event and could have an Earth directed component.

WATCH: https://youtu.be/GTK1kz5oGi8

A minor (S1) radiation storm is associated, with fast-moving particles already recorded moving past our planet. These solar particles are propelled into space by the x-ray flare

A moderate G2 geomagnetic storm caused by components of the CME produced by the flare is expected to impact our geomagnetic field and could lead to nice aurora at higher latitudes, sometime between the beginning of 16 July through 18 July 2017.

Stay tuned, and watch for Aurora!

https://youtu.be/GTK1kz5oGi8

http://Aurora.SunSpotWatch.com

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https://youtu.be/GTK1kz5oGi8

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We need patrons for SunSpotWatch.com - working on two projects http://nw7us.us/patron #hamr #SolarStorm
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Read it now: the official International Shortwave Broadcast Guide with my article, "Crash Course of Shortwave Propagation and Space Weather" - This book is now on Amazon.

Here is my short link to the Amazon Kindle page:

http://g.nw7us.us/isbgw2016

#SpaceWX #SpaceWeather #Propagation #ionosphere #science #hamradio #hamr #ARRL
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A Nuclear Fusion Light Show -- The Sun in 4k-UHD!

The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen each second.

The sun is always changing and NASA's Solar Dynamics Observatory is always watching. Launched on February 11, 2010, SDO keeps a 24-hour eye on the entire disk of the sun, with a prime view of the graceful dance of solar material coursing through the sun's atmosphere, the corona.

SDO captures images of the sun in 10 different wavelengths, each of which helps highlight a different temperature of solar material. Different temperatures can, in turn, show specific structures on the sun such as solar flares, which are gigantic explosions of light and x-rays, or coronal loops, which are stream of solar material travelling up and down looping magnetic field lines.

Scientists study these images to better understand the complex electromagnetic system causing the constant movement on the sun, which can ultimately have an effect closer to Earth, too. Flares and another type of solar explosion called coronal mass ejections can sometimes disrupt technology in space. Moreover, studying our closest star is one way of learning about other stars in the galaxy. NASA's Goddard Space Flight Center in Greenbelt, Md. built, operates, and manages the SDO spacecraft for NASA's Science Mission Directorate in Washington, D.C.

It is widely believed that the Sun's magnetic field is generated by electrical currents acting as a magnetic dynamo inside the Sun. These electrical currents are generated by the flow of hot, ionized gases in the Sun's convection zone.

We know a lot about the Sun's magnetic dynamo. It has a 22 year cycle. During the first half of the cycle, the Sun's magnetic north pole is in the northern hemisphere while the magnetic south pole is in the southern hemisphere. Right around the peak of the sunspot cycle (solar maximum), the magnetic poles flip or exchange places so that magnetic north is now located in the southern hemisphere. This flip occurs about every 11 years at solar maximum.

The 22 year magnetic cycle greatly influences the most prominent manifestation of the dynamo, sunspots and active regions, which migrate towards the solar equator from high latitudes over the course of the solar 11 year "sunspot cycle". Sunspots and Active Regions are manifestation of the magnetic field generated in the Sun's interior poking through the visible region of the atmosphere. Active regions are responsible for the production of intense and violent energy burst, called flares, and events where very large amounts of hot gas, trapped by the magnetic field of the active region, are released from the Sun's atmosphere and into space, called coronal mass ejections (CMEs).

Watch the movie, now! Here's the link: https://www.youtube.com/watch?v=sq4PlyNkm2Y

Credit: The SDO Team, Genna Duberstein and Scott Wiessinger, Producers

1st music:
The Big Decision by Audionautix is licensed under a Creative Commons Attribution license (https://creativecommons.org/licenses/by/4.0/)
Artist: http://audionautix.com/

Then:

Light Awash by Kevin MacLeod is licensed under a Creative Commons Attribution license (https://creativecommons.org/licenses/by/4.0/)
Source: http://incompetech.com/music/royalty-free/index.html?isrc=USUAN1100175
Artist: http://incompetech.com/

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